{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,25]],"date-time":"2026-06-25T16:08:24Z","timestamp":1782403704883,"version":"3.54.5"},"reference-count":46,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2024,10,6]],"date-time":"2024-10-06T00:00:00Z","timestamp":1728172800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"CONACYT","award":["CB-2015-01-258043"],"award-info":[{"award-number":["CB-2015-01-258043"]}]},{"name":"Fun- daci\u00f3n Miguel Alem\u00e1n Vald\u00e9s","award":["CB-2015-01-258043"],"award-info":[{"award-number":["CB-2015-01-258043"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Spinocerebellar ataxia type 7 (SCA7) is a rare genetic disease characterized by progressive cerebellar syndrome and macular degeneration. In a previous study, we clinically and genetically characterized a group of Mexican patients, which represented one of the largest cohorts of SCA7 patients worldwide and demonstrated that all patients had a unique genetic origin. Our laboratory developed a program for the diagnosis, medical care, and long-term follow-up of these patients living in Veracruz State, and in this report, we present an update to this research, covering 2013 to 2024. So far, we identified 172 SCA7 carriers, with a few cases outside Veracruz, and our data support that the length of the CAG repeat tract mainly determines disease severity and life expectancy, and accordingly, we define three different phenotypes, early-onset (EO), classical-onset (CO), and late-onset (LO), with EO patients showing the lowest life expectancy. Furthermore, we found that parental transmission of mutant alleles leads to increased CAG repeat instability, compared to maternal ones. Interestingly, a haplotype analysis revealed that patients outside Veracruz may have different genetic origins. In conclusion, longitudinal observations of SCA7 patients provide insight into the natural history of SCA7 and help to design strategies for diagnosis, genetic counseling, physical rehabilitation, and therapeutic alternatives.<\/jats:p>","DOI":"10.3390\/ijms251910750","type":"journal-article","created":{"date-parts":[[2024,10,7]],"date-time":"2024-10-07T06:23:18Z","timestamp":1728282198000},"page":"10750","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Current Overview of Spinocerebellar Ataxia Type 7 in Mexican Population: Challenges in Specialized Care for a Rare Disease"],"prefix":"10.3390","volume":"25","author":[{"given":"C\u00e9sar M.","family":"Cerecedo-Zapata","sequence":"first","affiliation":[{"name":"Laboratory of Genomic Medicine, Department of Genetics, National Rehabilitation Institute Luis Guillermo Ibarra Ibarra (INRLGII), Mexico City 14389, Mexico"},{"name":"Rehabilitation and Special Education Center of Veracruz (CRISVER), Xalapa de Enriquez 91097, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3281-4757","authenticated-orcid":false,"given":"Yessica S.","family":"Tapia-Guerrero","sequence":"additional","affiliation":[{"name":"Laboratory of Genomic Medicine, Department of Genetics, National Rehabilitation Institute Luis Guillermo Ibarra Ibarra (INRLGII), Mexico City 14389, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3715-1921","authenticated-orcid":false,"given":"Jos\u00e9 A.","family":"Ram\u00edrez-Gonz\u00e1lez","sequence":"additional","affiliation":[{"name":"Laboratory of Genomic Medicine, Department of Genetics, National Rehabilitation Institute Luis Guillermo Ibarra Ibarra (INRLGII), Mexico City 14389, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aranza","family":"Meza-Dorantes","sequence":"additional","affiliation":[{"name":"Department of Bioengineering, School of Engineering, Tecnologico de Monterrey, Campus Ciudad de M\u00e9xico, Mexico City 14380, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karla N.","family":"Tercero-P\u00e9rez","sequence":"additional","affiliation":[{"name":"Rehabilitation and Special Education Center of Veracruz (CRISVER), Xalapa de Enriquez 91097, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6147-4109","authenticated-orcid":false,"given":"Hern\u00e1n","family":"Cort\u00e9s","sequence":"additional","affiliation":[{"name":"Laboratory of Genomic Medicine, Department of Genetics, National Rehabilitation Institute Luis Guillermo Ibarra Ibarra (INRLGII), Mexico City 14389, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3442-1826","authenticated-orcid":false,"given":"Araceli","family":"Guerra-Grajeda","sequence":"additional","affiliation":[{"name":"Laboratory of Genomic Medicine, Department of Genetics, National Rehabilitation Institute Luis Guillermo Ibarra Ibarra (INRLGII), Mexico City 14389, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ilse H.","family":"Ortega-Ibarra","sequence":"additional","affiliation":[{"name":"Instituto de Salud P\u00fablica, Universidad Veracruzana, Xalapa de Enriquez 91000, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gabriela","family":"Gatica-Ramos","sequence":"additional","affiliation":[{"name":"Instituto de Salud P\u00fablica, Universidad Veracruzana, Xalapa de Enriquez 91000, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alfredo","family":"Poblete-Velazquez","sequence":"additional","affiliation":[{"name":"Hospital Regional de Xalapa \u201cDr. Luis F. Nach\u00f3n\u201d, Secretaria de Salud de Veracruz, Xalapa de Enriquez 91130, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Norberto","family":"Leyva-Garc\u00eda","sequence":"additional","affiliation":[{"name":"Laboratory of Genomic Medicine, Department of Genetics, National Rehabilitation Institute Luis Guillermo Ibarra Ibarra (INRLGII), Mexico City 14389, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luis","family":"Vel\u00e1zquez-P\u00e9rez","sequence":"additional","affiliation":[{"name":"Science Cuban Academy, La Havana 12400, Cuba"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bulmaro","family":"Cisneros","sequence":"additional","affiliation":[{"name":"Department of Genetics and Molecular Biology, Center of Research and Advanced Studies (CINVESTAV-IPN), Mexico City 07360, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4399-4618","authenticated-orcid":false,"given":"Jonathan J.","family":"Maga\u00f1a","sequence":"additional","affiliation":[{"name":"Laboratory of Genomic Medicine, Department of Genetics, National Rehabilitation Institute Luis Guillermo Ibarra Ibarra (INRLGII), Mexico City 14389, Mexico"},{"name":"Department of Bioengineering, School of Engineering, Tecnologico de Monterrey, Campus Ciudad de M\u00e9xico, Mexico City 14380, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,10,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"65","DOI":"10.1038\/ng0997-65","article-title":"Cloning of the SCA7 gene reveals a highly unstable CAG repeat expansion","volume":"17","author":"David","year":"1997","journal-title":"Nat. Genet."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"165","DOI":"10.1093\/hmg\/7.2.165","article-title":"Molecular and clinical correlations in autosomal dominant cerebellar ataxia with progressive macular dystrophy (SCA7)","volume":"7","author":"David","year":"1998","journal-title":"Hum. Mol. Genet."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"176","DOI":"10.1007\/s12311-012-0412-4","article-title":"Spinocerebellar Ataxia Type 7: Clinical Course, Phenotype\u2013Genotype Correlations, and Neuropathology","volume":"12","author":"Horton","year":"2013","journal-title":"Cerebellum"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"911","DOI":"10.1007\/s004150170082","article-title":"Striking anticipation in spinocerebellar ataxia type 7: The infantile phenotype","volume":"248","author":"Frenken","year":"2001","journal-title":"J. Neurol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1016\/S0022-510X(99)00176-8","article-title":"Spinocerebellar ataxia type 7 (SCA7)\u2014correlations between phenotype and genotype in one large Belgian family","volume":"168","author":"Martin","year":"1999","journal-title":"J. Neurol. Sci."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1007\/s10048-014-0424-y","article-title":"A comprehensive clinical and genetic study of a large Mexican population with spinocerebellar ataxia type 7","volume":"16","year":"2015","journal-title":"Neurogenetics"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"902","DOI":"10.1007\/s12311-013-0505-8","article-title":"Origin of the Spinocerebellar Ataxia Type 7 Gene Mutation in Mexican Population","volume":"12","author":"Cisneros","year":"2013","journal-title":"Cerebellum"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"351","DOI":"10.1002\/1096-8628(20001211)95:4<351::AID-AJMG10>3.0.CO;2-R","article-title":"Frequency of spinocerebellar ataxia types 1, 2, 3, 6, and 7 in Australian patients with spinocerebellar ataxia","volume":"95","author":"Storey","year":"2000","journal-title":"Am. J. Med. Genet."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1186\/s40673-017-0075-5","article-title":"Clinical and genetic analysis of spinocerebellar ataxia type 7 (SCA7) in Zambian families","volume":"4","author":"Atadzhanov","year":"2017","journal-title":"Cerebellum Ataxias"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"889","DOI":"10.1038\/sj.ejhg.5200392","article-title":"Multiple origins of the spinocerebellar ataxia 7 (SCA7) mutation revealed by linkage disequilibrium studies with closely flanking markers, including an intragenic polymorphism (G3145TG\/A3145TG)","volume":"7","author":"Stevanin","year":"1999","journal-title":"Eur. J. Hum. Genet."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"159","DOI":"10.1111\/cge.12114","article-title":"Analysis of CAG repeats in five SCA loci in Mexican population: Epidemiological evidence of a SCA7 founder effect","volume":"85","year":"2014","journal-title":"Clin. Genet."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Bouzid, F.Z., Mansouri, M., Abdelaziz, C., Louhab, N., Bernard, S., Strubi-Vuillaume, I., Dafir, K., and Aboussair, N. (2021). Spinocerebellar ataxia Type 7: Clinical and genetic study of a new Moroccan family (case report). Pan Afr. Med. J., 38.","DOI":"10.11604\/pamj.2021.38.162.27262"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"415","DOI":"10.1111\/j.1399-0004.2006.00680.x","article-title":"Origin of the SCA7 gene mutation in South Africa: Implications for molecular diagnostics","volume":"70","author":"Greenberg","year":"2006","journal-title":"Clin. Genet."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"75","DOI":"10.1016\/j.jns.2015.04.053","article-title":"Evidence for a common founder effect amongst South African and Zambian individuals with Spinocerebellar ataxia type 7","volume":"354","author":"Smith","year":"2015","journal-title":"J. Neurol. Sci."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"918","DOI":"10.1038\/sj.ejhg.5200557","article-title":"Evidence for a common Spinocerebellar ataxia type 7 (SCA7) founder mutation in Scandinavia","volume":"8","author":"Jonasson","year":"2000","journal-title":"Eur. J. Hum. Genet."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1666","DOI":"10.1212\/WNL.51.6.1666","article-title":"Incidence of dominant spinocerebellar and Friedreich triplet repeats among 361 ataxia families","volume":"51","author":"Moseley","year":"1998","journal-title":"Neurology"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1081","DOI":"10.1212\/WNL.51.4.1081","article-title":"Molecular and clinical studies in SCA-7 define a broad clinical spectrum and the infantile phenotype","volume":"51","author":"Benton","year":"1998","journal-title":"Neurology"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"708","DOI":"10.1007\/s12311-022-01442-z","article-title":"An Exploratory Survey on the Care for Ataxic Patients in the American Continents and the Caribbean","volume":"22","author":"Jardim","year":"2022","journal-title":"Cerebellum"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"446","DOI":"10.1007\/s12311-020-01109-7","article-title":"Founder Effects of Spinocerebellar Ataxias in the American Continents and the Caribbean","volume":"19","author":"Martins","year":"2020","journal-title":"Cerebellum"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"601","DOI":"10.1007\/s12311-018-0947-0","article-title":"Oxidative Stress in Spinocerebellar Ataxia Type 7 Is Associated with Disease Severity","volume":"17","author":"Cisneros","year":"2018","journal-title":"Cerebellum"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"173","DOI":"10.1159\/000370239","article-title":"Spinocerebellar Ataxia Type 7: A Neurodegenerative Disorder with Peripheral Neuropathy","volume":"73","author":"Cisneros","year":"2015","journal-title":"Eur. Neurol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"185","DOI":"10.1159\/000517213","article-title":"Involvement of the Auditory Pathway in Spinocerebellar Ataxia Type 7","volume":"20","year":"2020","journal-title":"Neurodegener. Dis."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"123.e1","DOI":"10.1016\/j.jvoice.2016.01.010","article-title":"Voice Alterations in Patients with Spinocerebellar Ataxia Type 7 (SCA7): Clinical-Genetic Correlations","volume":"31","author":"Cisneros","year":"2017","journal-title":"J. Voice"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"6106","DOI":"10.1007\/s12035-019-1480-y","article-title":"Wide Profiling of Circulating MicroRNAs in Spinocerebellar Ataxia Type 7","volume":"56","author":"Cisneros","year":"2019","journal-title":"Mol. Neurobiol."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Nambo-Venegas, R., Valdez-Vargas, C., Cisneros, B., Palacios-Gonz\u00e1lez, B., Vela-Amieva, M., Ibarra-Gonz\u00e1lez, I., Cerecedo-Zapata, C.M., Mart\u00ednez-Cruz, E., Cort\u00e9s, H., and Reyes-Grajeda, J.P. (2020). Altered Plasma Acylcarnitines and Amino Acids Profile in Spinocerebellar Ataxia Type 7. Biomolecules, 10.","DOI":"10.3390\/biom10030390"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"397","DOI":"10.1007\/s12311-019-1006-1","article-title":"Effects of Physical Rehabilitation in Patients with Spinocerebellar Ataxia Type 7","volume":"18","author":"Cisneros","year":"2019","journal-title":"Cerebellum"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"494","DOI":"10.1016\/j.ymgme.2010.12.001","article-title":"Experience over fifteen years with a protocol for predictive testing for Huntington disease","volume":"102","author":"Dufrasne","year":"2011","journal-title":"Mol. Genet. Metab."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"55","DOI":"10.1007\/s100720170044","article-title":"Presymptomatic tests in Huntington\u2019s disease and dominant ataxias","volume":"22","author":"Cannella","year":"2001","journal-title":"Neurol. Sci."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"717","DOI":"10.1089\/gtmb.2009.0032","article-title":"Presymptomatic Diagnosis in Huntington\u2019s Disease: The Mexican Experience","volume":"13","author":"Alonso","year":"2009","journal-title":"Genet. Test. Mol. Biomark."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"165","DOI":"10.1016\/j.brainresbull.2006.10.023","article-title":"Predictive testing for Huntington\u2019s disease","volume":"72","author":"Tibben","year":"2007","journal-title":"Brain Res. Bull."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"518","DOI":"10.1111\/cge.12142","article-title":"The Cuban program for predictive testing of SCA2: 11 years and 768 individuals to learn from","volume":"83","year":"2013","journal-title":"Clin. Genet."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"469","DOI":"10.1007\/s10897-006-9083-y","article-title":"Psychological Follow-up of Presymptomatic Genetic Testing for Spinocerebellar Ataxia Type 2 (SCA2) in Cuba","volume":"16","author":"Paneque","year":"2007","journal-title":"J. Genet. Couns."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"241","DOI":"10.1007\/s10897-010-9347-4","article-title":"Ethical Dilemmas in Genetic Testing: Examples from the Cuban Program for Predictive Diagnosis of Hereditary Ataxias","volume":"20","author":"Mesa","year":"2011","journal-title":"J. Genet. Couns."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"101","DOI":"10.1007\/s10897-011-9383-8","article-title":"Presymptomatic Testing for Neurogenetic Diseases in Brazil: Assessing Who Seeks and Who Follows through with Testing","volume":"21","author":"Rodrigues","year":"2012","journal-title":"J. Genet. Couns."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1188","DOI":"10.1038\/ejhg.2010.10","article-title":"Consensus and controversies in best practices for molecular genetic testing of spinocerebellar ataxias","volume":"18","author":"Sequeiros","year":"2010","journal-title":"Eur. J. Hum. Genet."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"295","DOI":"10.1038\/ejhg.2008.164","article-title":"Decreasing uptake of predictive testing for Huntington\u2019s disease in a German centre: 12 years\u2019 experience (1993\u20132004)","volume":"17","author":"Bernhardt","year":"2009","journal-title":"Eur. J. Hum. Genet."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"522","DOI":"10.1136\/jmg.39.7.522","article-title":"Predictive testing in the context of pregnancy: Experience in Huntington\u2019s disease and autosomal dominant cerebellar ataxia","volume":"39","author":"Lesca","year":"2002","journal-title":"J. Med. Genet."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"221","DOI":"10.1111\/j.1399-0004.2012.01900.x","article-title":"Recommendations for the predictive genetic test in Huntington\u2019s disease","volume":"83","author":"MacLeod","year":"2013","journal-title":"Clin. Genet."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"92","DOI":"10.1111\/j.1399-0004.2008.01044.x","article-title":"Predictive testing for Huntington disease in a developing country","volume":"75","author":"Futter","year":"2009","journal-title":"Clin. Genet."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"297","DOI":"10.1111\/j.1399-0004.2006.00606.x","article-title":"Psychological aspects of pre-symptomatic testing for Machado\u2013Joseph disease and familial amyloid polyneuropathy type I","volume":"69","author":"Rolim","year":"2006","journal-title":"Clin. Genet."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"589","DOI":"10.1093\/brain\/121.4.589","article-title":"The natural history of degenerative ataxia: A retrospective study in 466 patients","volume":"121","author":"Klockgether","year":"1998","journal-title":"Brain"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"1035","DOI":"10.1212\/WNL.0b013e31822e7ca0","article-title":"The natural history of spinocerebellar ataxia type 1, 2, 3, and 6","volume":"77","author":"Jacobi","year":"2011","journal-title":"Neurology"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"108","DOI":"10.1016\/S1525-1578(10)60689-7","article-title":"Diagnosis of Five Spinocerebellar Ataxia Disorders by Multiplex Amplification and Capillary Electrophoresis","volume":"4","author":"Dorschner","year":"2002","journal-title":"J. Mol. Diagn."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"128","DOI":"10.2353\/jmoldx.2006.050043","article-title":"Large Pathogenic Expansions in the SCA2 and SCA7 Genes Can Be Detected by Fluorescent Repeat-Primed Polymerase Chain Reaction Assay","volume":"8","author":"Cagnoli","year":"2006","journal-title":"J. Mol. Diagn."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"1717","DOI":"10.1212\/01.wnl.0000219042.60538.92","article-title":"Scale for the assessment and rating of ataxia","volume":"66","author":"Baliko","year":"2006","journal-title":"Neurology"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"982","DOI":"10.1212\/01.wnl.0000325057.33666.72","article-title":"Spinocerebellar ataxia types 1, 2, 3, and 6","volume":"71","author":"Coudert","year":"2008","journal-title":"Neurology"}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/25\/19\/10750\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T16:11:28Z","timestamp":1760112688000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/25\/19\/10750"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,10,6]]},"references-count":46,"journal-issue":{"issue":"19","published-online":{"date-parts":[[2024,10]]}},"alternative-id":["ijms251910750"],"URL":"https:\/\/doi.org\/10.3390\/ijms251910750","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,10,6]]}}}